Abstract
In this study a hybrid coupling method for the dynamic analysis of dam-foundation-reservoir system has been developed. With this method, 3-D dynamic analyses were carried out to simulate the actual earthquake behaviors of an existing concrete gravity dam at the Kushiro-oki Earthquake (1993. M7. 8). As the results, the dynamic shear modulus of the dam was evaluated to be 11, 032N/mm2, and the material damping factors of the dam and the foundation are evaluated to be 5%. With the identified analytic model, the revaluation of the seismic stability of the dam against very strong earthquake was done considering the non-linearity of dam and foundation materials. Furthermore, it is pointed out that the interaction between dam and reservoir exerts an important effect on the dam responses, and the added mass method can not give an accurate solution.
